[Gmsh] How to post-process from the command line

[Aimery ASSIRE]

>> 4.2) When I call :
>>  gmsh DAAAGI.pos stt.geo -0
>> gmsh runs, as expected, in batch mode but generates no .png file.
>> Did I miss something on how to print any chosen view ?
>
> The problem is that Gmsh cannot save an image if the OpenGL window is
> not shown on screen. There are ways to do offscreen rendering, but last
> time I looked it was very complicated and not easily portable across
> different architectures.

Hi,

Under Linux, you can use a virtual X framebuffer, such Xvfb 
(http://www.xfree86.org/4.0.1/Xvfb.1.html) or vnc-server.

Just configure and launch Xvfb (or Vnc) and you can use gmsh -display 
IP_adresse:0 (or another display number).

If you are on Windows, you can forward X on an unix running a Virtual 
Framebuffer : just set his ip and display number...

Remark : when using VNC, you need to modify ~/.vnc/xstartup : you need to 
use another Window manager than twm (mwm, windowmaker, etc... ) because need 
you click to position any new window, that is no good when using a virtual 
xserver... :)

Aimery